The world's first "vertical street" will soon be built in Melbourne, Australia.

Every sixth floor of the 35-story building will have gardens capable of growing trees up to 10 metres tall and the entire building will be boasting the very latest in green technology.

While roof gardens and landscaped balconies have been constructed in the past, project architect Robert Caulfield of CK Designworks, Melbourne, says this is the first time that five high-rise communal gardens have been attempted in the same building.

To achieve this feat, purpose-built planter boxes allowing tree roots to grow in the confined 120-square-metre gardens, and structural supports that hold the weight of the soil and trees will be used. Heat-reflective glass and solar-powered lighting will also be incorporated.

Since the site is a mere 360 square metres, the building's external walls — more than 8000 square metres — will be used to catch rainwater. "This is unusual," says Caulfield. Normally strong winds "just blow the rain off the building".

But, in this development, triangular balconies and a jagged façade are used to reduce the sideways movement of the wind, minimising the water escaping from the side. The catchment will feed into the building's water supply to be used for garden watering and toilet flushing.

The heating and cooling systems are also designed around the gardens. Conventional buildings either use individual air-conditioner systems,or long pipes that pump hot or cold water down the entire building. Both systems are inefficient, either wasting energy by heating one apartment at a time, or losing heat as water is moved great distances.

"We have a hybrid version," says Caulfield. A cooling system installed in each garden will pump water to only six floors, three above and three below. "The short pipe minimises heating or cooling loss," he says.

The building, which will house shops, offices and 154 apartments, will be completed by 2014.

And with horizontal space in demand worldwide, our vertical world is sure to expand. Caulfield's next project is building vertical factories in Nanjing, China.